波浪环境下垂直射流动量积分模型  

A momentum integral model for vertical jet in wavy environment

作　　者：胡飞[1,2] 陈永平[1,2] 徐振山[1,2] 张长宽[2] 

机构地区：[1]河海大学水文水资源与水利工程科学国家重点实验室,江苏南京210098 [2]河海大学港口海岸与近海工程学院,江苏南京210098

出　　处：《水利学报》2013年第9期1058-1063,1070,共7页Journal of Hydraulic Engineering

基　　金：国家重点基础研究发展计划(973计划)课题(2010CB429001);水文水资源与水利工程科学国家重点实验室基本科研业务费自主研究项目(2011585812)

摘　　要：建立了一个基于动量积分法的射流数学模型,以模拟波浪作用下垂直射流近区段的扩散过程。采用自然坐标系统,假定射流流场保持瞬时稳定且相对速度剖面保持高斯分布,考虑波浪作用影响对卷吸函数进行了必要修正,采用拉格朗日追踪法和四阶龙格库塔法,对多个波浪工况下的垂直射流进行了数值计算。结果表明,在微幅波作用下射流的卷吸和掺混作用有所加强,使得射流轴线平均速度衰减加快,而射流影响范围相应增大。通过卷吸函数的波浪修正后,模型中射流垂向平均速度和射流半宽沿轴线的变化与物理实验的测量结果基本一致。A momentum integral model is developed to analyze the hydrodynamic characteristics of a verti- cal jet discharged into a wavy environment. Natural coordinate system is adopted, and it＇s assumed that the flow field is instantaneously steady and the transverse profiles of jet velocity are Gaussian-type profile. The model also makes some modification to the entrainment function. By the Lagrangian method and the fourth-order R-K approach, vertical jets in small-amplitude waves are simulated. The results show that the entrainment effect is significantly enhanced, resulting in a wider jet width and a faster decay of centerline velocity, compared to the stagnant conditions. The model findings fit well with the results obtained from the experiments conducted earlier.

关 键 词：波浪环境 垂直射流 动量积分法 波浪强制卷吸 

分 类 号：TV139.2[水利工程—水力学及河流动力学]